As I'm not a sooth sayer, I'm unable to guess which is the used operating system.
The described behavior surfaced here and there since at least january 2009.
We never got a clear explanation of this oddity.
Try to export in an Excel file.
You may also try to save as a Numbers '08 file.
Try also to export as csv.
After a system reboot, I guess that you will be able to open the 'old' version.
For safe, Apply a Copy Paste into a fresh document.
This would be useful to retrieve the formulas.
Then, open the Excel or the Numbers '08 or the csv file to copy paste the datas in the cells supposed to store raw datas. The formulas will apply upon the new set of datas.
Yvan KOENIG (VALLAURIS, France) mardi 15 janvier 2011 21:00:20
iMac 21”5, i7, 2.8 GHz, 4 Gbytes, 1 Tbytes, mac OS X 10.6.8 and 10.7.2
My iDisk is : <http://public.me.com/koenigyvan>
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